Bone mass decreases with increasing age in both men and women. Factors that influence the rate of bone loss include age and gender, as well as race. Bone loss in African American men and women is slower than in Caucasian men and women. Bone density scans, which have become the "gold standard" for measuring bone loss, have not adequately addressed gender- based differences in osteopenia in an aging population. Furthermore, the comparison of African American bone loss rates with those of Caucasians has not received adequate study. The goal of this protocol is to correlate bone mineral density (BMD) at two anatomical sites with serum and urine markers of skeletal turnover over a period of 24 months in a population of aging African American and Caucasian men and postmenopausal women. During this reporting period, the final five patients were studied. The results of the entire study indicate that while DEXA scans may be the gold standard for staging bone loss, the urinary marker deoxypyridinoline appears to be the most informative biomarker for dynamic bone loss. The serum markers osteocalcin and procollagen type I carboxyl terminal peptide exhibited a lack of correlation with ethnicity and gender. Because of limited enrollment in this study (70 total), the results lack the power to define statistically meaningful differences between the multiple subgroups stratified by age, gender and ethnicity. The results do confirm previous observations of higher bone mass and reduced rate of bone loss in the African American study population.